The beating heart of the effort to resist President Donald Trump will descend on Atlanta on Thursday with a four-day conference of the nation’s leading liberal activists and politicians.

The mission of the Netroots Nation event is to energize a legion of new activists ahead of next year’s midterms, derail Trump’s agenda and lay the groundwork to oust him in 2020. And they’ll have backup from U.S. Sen. Elizabeth Warren and former Vice President Al Gore, as well as Georgia’s two Democratic candidates for governor, Stacey Abrams and Stacey Evans.

Part pep rally and part insurgency training, the conference includes nearly 200 panels and training sessions designed to teach progressive activists how to reclaim state legislatures, advance LGBT rights in the South and master social media strategy.

Others aim to encourage liberals to run for office, whether they challenge incumbent Republicans or establishment Democrats. One even advises activists on how — and why — they should take over their local Democratic Party to bring a more liberal bent.

And then there are discussions focused on sharpening lessons from Democrat Hillary Clinton’s defeat in November. One trains candidates and activists to secure their websites “against the Internet’s wretched hive of scum and villainy.” Another panel counsels strategists on how to combat fake news.[…]

Mary Rickles, a Netroots spokeswoman, said the event will feature the most training sessions in its history. About half of its attendees, she added, have never before attended the conference.

“We want to shape the debate and go on the offensive to form a vision for the resistance movement — and beyond the resistance,” she said. “We have an influx of new attendees and new partnerships. And a lot of progressive groups that have been involved in Netroots for years have stepped it up this time.”

Studded throughout the four days are regional meetings intent on plotting a course for Democrats in Georgia, where Republicans have consolidated control despite liberal dreams of flipping the state, and other parts of the South.

One panel, to be headlined by Clarkston Mayor Ted Terry, seems aimed at convincing activists that the South isn’t a lost cause. Terry said he’ll talk about how cities can be “truer laboratories of democracy than states” and use his DeKalb County city — which recently approved the state’s most liberal marijuana policy — as proof.

“As a progressive local mayor in a red state, I don’t have to wait for the next governor or Congress to take action on affordable housing, clean energy or criminal justice reforms,” Terry said. “So the power in the South, from my perspective, is at the local level where home rule can be broad-ranging.”